This application addresses broad Challenge Area 01: Behavior, Behavioral Change, and Prevention, and specific Challenge Topic 01-OD-101: Test default options to promote healthier behaviors. We propose a set of three related studies that target two critical locations for decision- making about food: the supermarket and the home. The first two studies focus on the supermarket environment to determine if setting new defaults - nutritional information or subsidies and/or taxes combined with nutrition information - encourage purchases of healthier food. The first study utilizes scanner data from before and after the implementation of an innovative supermarket point-of-purchase nutrition information program. Specifically, we test whether and how the implementation of the nutrition information program affected purchases of less healthy and more healthy foods, and how the implementation affected total store sales. We hypothesize that nutrition information decreases the sale of less healthy foods and increases the sale of healthy foods;the net effect on store sales is an empirical question. The second study conducts randomized controlled trials to measure the responsiveness of supermarket purchases to taxes on unhealthy foods and subsidies for healthy foods combined with point of purchase information on nutrition. We hypothesize that taxes will decrease purchases of unhealthy foods less than subsidies will increase purchases of healthy foods for psychological reasons, but the exact magnitude of the price elasticities will be of great interest for several reasons, including (1) a better understanding of consumer behavior regarding food and (2) projecting the impact of taxes and subsidies to encourage healthy eating and prevent obesity. We also hypothesize that the effect of taxes or subsidies will have a larger impact on increasing healthy food and reducing unhealthy food purchases when combined with nutrition information. The third study focuses on the home environment and will determine if setting new defaults - smaller plates, smaller utensils, and serving foods from kitchen counters rather than kitchen tables - influences the quantity of food people eat during meals at home. We hypothesize that the use of smaller plates will lead to lower consumption and therefore weight loss (in adults) As we expect children to gain weight at they grow, we will track BMI in relation to standard height/weight tables for the children. Collectively, these three studies will greatly enhance our understanding of how nutritional gatekeepers make decisions in two critical venues (the supermarket and the home) and will inform public health policy to promote healthy eating and to prevent obesity. PUBLIC HEALTH RELEVANCE: This project will test the effectiveness of combining simple health based information with a tax levied on less healthy foods and subsidy on more healthy foods in trying to improve diets. Several studies have shown the taxes by themselves to be less effective. Further, we will examine the impact of home serving behaviors on food consumption.